Pedal-action for pianos.



No. 7|2,774. Phtentod m. 4, I902.

J. mannonr.

PEDAL AGTIUN FOB HANDS.

1mm M J'uno 20, 1001.

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IN V II 8 nv VENTOH A TTORN E Y.

UNITED STATES PATENT OFFICE.

JOHN DIERDORF, OF INDIANAPOLIS, INDIANA.

PEDAL-ACTION FOR/PIANOS.

SPECIFICATION forming part of Letters Patent No. 712,774, dated November4, 1902.

Application filed June 20, 1901. Serial No. 65,258. (No model.)

To to whom it may concern.-

Be it known that I, J OHN DIERDORF, a citizen of the United States,residing at Indianapolis, in the county of Marion and State of Indiana,have invented certain new and useful Improvements in Pedal-Actions forPianos, of which the following is a specification.

My present invention consists in certain improvements in pedal-actionsfor pianos in which simplicity in mechanical construction, durability,and together with which I procure better results than those that formthe subject-matter of Letters Patent of the United States No. 651,749,issued on my application and bearing the date of June 10, 1900.

In my present application I have dispensed with the numerous rods,bell-cranks, and standards which were employed in my before-mentionedpatent and substituted therefor a bar or beam having an extendedintegral leg, the heel of which forms the fulcrum for said beam. Thenumber of the wearingpoints in this construction are greatly reduced,thus reducing the maintenance thereof, while the longevity andefiiciency of the action is obviously increased.

My invention is applicable to all styles of upright pianos withoutchanging any of their parts.

Referring to the accompanying drawings, which are made a part hereof,and on which similar numerals of reference indicate similar parts,Figure 1 is a front elevation of the lower portion of a piano in whichthe front wall thereof, below the pianoforte, is broken away, thus notonly exposing the interior of the piano, but showing the exact locationof the different parts of my invention in their assembled and operatingposition. Fig. 2 is a fragmentary detail, on an enlarged scale, of thestandard which forms the pivotal hearing for the pedals. Fig. 3 is aplan view of Fig. 2. Fig. 4 is an enlarged view, in side elevation, ofthe bar and pedal attachment, the surrounding portions in the figurebeing removed, so as to leave a free and unobstructed view. Fig. 5 is avertical transverse section of the bar and shows the foot in elevation,the heel of said footbeing recessed, all as seen when looking in thedirection indicated by the arrows on the dotted line 5 5 in Fig. 4; andFig. 6 is a vertical transverse section of the bar and shows theleaf-spring in end elevation, all as seen when looking in thedirectionindicated by the arrows on the dotted line 6 6 in Fig. 4.

In the drawings, 1 represents the main body of the piano, the style ofwhich is old and well known. 2 is the floor of the piano. 3 are thecasters on which the piano is mounted.etdesignatestheverticaldamper-rods, which are common, in all uprightpianos and are usually three in number, two of which are located in oneend of the piano and one in the otherf The damper-rods 4: extend to theupper portion of the piano, where they connect with the dampers whichregulate and control the volume of tone produced by the instrument.These rods, however, are old and will be hereinafter only incident-allyreferred to in connection with other parts throughout the specification.

To actuate the damper-rods 4 in a simple and effective manner is themain object of my invention, and which I accomplish by providing thebeam 5,.which extends from the center of the piano to the inner endsthereof, and at which point they engage with the lower ends of thevertical damper-rods 4 by means of. pins in the ends of said rods andthe eyes formedin the ends of the beams 5. As before stated, there areusually three pedals and damper-rods in a piano, and as they areconnected by means ofthe beams 5, which are of similar construction, thedescription of one will suffice for the others.

The beam 5 extendsfrom the center of the piano to its inner ends. Theinner end of the beam 5 is supplied with an aperture, which is suspendedin a perpendicular manner over the pedal, the eye in the bar or beamadapted to receive the vertical rod 6, through which the beam and pedalsare connected together. As the pedals are in the center of the piano, itplaces thernconveniently for the operator, who when desiring therequisite tone places the foot on the desired pedal, and through the rod6 and the beam 5 and damper-rods 4 the dampers proper are actuated.

The beam 5 has an integral extended leg 8, foot 9, and heellO. Theintegral leg 8 is located approximately one-third of the beams lengthfrom its inner end. This, however,

varies in the different widths of pianos where longer beams arerequired. It will be noted (see Figs. 1 and 4) that the beam 5 rides onthe heel 10, which heel is recessed, leaving the boss 21 at each side.The bosses 21 engage with drilled holes in the floor 2. By thisarrangement I decrease the beams contact-surface with the floor, andconsequently lessen the friction, which is desirable. The extendedbosses 21 also facilitate the work in placing the action inalreadyconstructed pianos, as the work of boring the holes is less thancutting a groove, which the other construction would require were theheel level on the bottom.

The extended integral foot 9 on the leg 8 is on an inclination slightlyabove a rightangle plane of the leg 8 and which places the sole of thefoot on an incline when the beam 5 stands in its normal position. Thedilference between the sole of the foot and the floors surface regulatesor limits the downward stroke of the beam 5.

A transverse groove 11 is cut into the'upper surface of the foot 9,which groove forms a seat for the leaf-spring 12. The spring 12 is bent,as shown in Figs. 1 and 4, and is recessed at the rear end, which leavesthe extended teeth 13, which are forced into the floor when the tensionis applied by driving the screw 50, whichpasses through an aperture inthe spring 12, and by drawing or driving said screw I procure therequisite pressure on the beam 5.

The pedals 7 are of the old and well-known variety except that they havetheirrear end slotted and which slots fitoveraspecially-constructedstandard 16. A pin 15 passes transversely through the pedals and slotsand engages with a recess in the standard, which connection forms thepivotal point for the pedal and the construction of which will now bedescribed.

A standard 16 is provided for each pedal and each has a horizontal slot17 cut into its front surface, which terminates in a recess 18. Thestandard 16 has an extended base 19 and a downward-extending integralscrew 20, by which it is secured to the floor 2. When the standard ispositioned to prevent it from turning, I form a notch 25 on each side ofthe base 19 and drive a small screw through the same.

As before stated, the slotted ends of the pedals carry the transversepins 15, which pins are inserted into the horizontal slots 17 in thestandards 16, the slots 17 terminating in recesses 18 and form the seatfor the pins 15. To prevent the disengagement of the parts, I providethe thumb-screw 22, which passes through the upper portion of thestandards in a vertical manner and seats itself on the transverse pins15. The thumb-screws are also provided with the jam-nut 23, which seatthemselves on the standards 16 when the same have been adjusted.

Having thus fully described my said invention, what I desire to secureby Letters Patent is- In a pedal-action for pianos, in combination withthe main piano-body, beams mounted therein which carry integrally-formedlegs the heels of which form the fulcrum therefor, feet integral withthe legs the faces of which are above a right-angle plane of the legsside, transverse grooves out into the surfaces of the feet, springsseated at one end in the transverse grooves while the other ends carryteeth which engage with the floor,screws passing vertically throughapertures in the springs and engaging with the floor,whereby therequisite tension for the beams is procured, substantially as shown andfor the-purposes set forth.

In witness whereof I have hereunto set my hand and seal, atIndianapolis, Indiana, this 7th day of January, A. D. 1901.

JOHN DIERDORF.

Witnesses:

F. W. WOERNER, CHAS. O. TOPP.

